WASHINGTON — The Lord’s Prayer filled the marble dome of the Russell Senate Office Building on Thursday as 70 Catholic sisters, clergy and parishioners were led away in handcuffs. “Forgive us our trespasses,” the demonstrators recited. “As we forgive those who trespass against us.”

On a day they dubbed the “Catholic Day of Action,” hundreds of Catholics gathered outside the Capitol to protest the Trump administration’s immigration policies and its treatment of migrants.